The present invention relates to a device by sprinkler nozzle, intended for use in a sprinkler system. In usual manner the sprinkler nozzle comprises a sprinkler nozzle housing with a passage therethrough for liquid, and a sprinkler nozzle pin arranged in the passage in the sprinkler nozzle housing. The sprinkler nozzle is activated to sprinkle liquid by displacement of the sprinkler nozzle pin to a position in which the passage in the sprinkler nozzle housing is opened.
The helicopter traffic in connection with the production of petroleum off shore has given rise to strict requirements to the fire fighting systems disposed on the helipads of the installations. Besides, it is expected that the requirements will be tightened, with, among other things, specifications that a possible fire shall be extinguished within a very short time, while at the same time the temperature at the fire area is to be kept down. Likewise, that the fire extinguishing liquid shall be spread in the specified manner independent of the intensity of the fire and the prevailing weather conditions. Known fire fighting systems may consist of a number of deluge guns disposed around the helipad, sprinkler system mounted into the helipad, or as a combination of both deluge guns and sprinkler system.
Practice has shown that known systems for fire fighting, that be deluge guns or sprinkler systems, are absolutely not unproblematic in use. Tightened requirements to the fire fighting system will worsen the situation further. As for the deluge guns, it may be mentioned as a defect that they are difficult to operate manually, because of high temperature close to the fire, the extinguishing liquid from the guns undesirably flushes other parts of the installation with burning petrol, the wind carries the extinguishing liquid away from the fire area, or that such guns hardly permit automatic operation in a fully satisfactory manner. As to sprinkler plants, it may be mentioned as a defect that known sprinkler nozzles are not capable of spreading the fire extinguishing liquid in such amounts that the fire is extinguished quickly enough, of keeping the temperature by the fire low enough, or of spreading the liquid to a sufficient height from and to the sides of the outlet of the sprinkler nozzle.
The main object of the present invention is to provide a device by a sprinkler nozzle which is of sufficiently large capacity for the sprinkler plant to be able to extinguish a possible fire within a very short period of time, while at the same time the temperature in the fire area is to be kept down. A further object is that the fire extinguishing liquid is to be sprayed up to a minimum height above, and to a minimum lateral distance from the outlet of the sprinkler nozzle. This is realised by means of the present device by sprinkler nozzle, in which the particularity is that the pin of the sprinkler nozzle is constituted by an inner sprinkler nozzle pin part which is fixed to the sprinkler nozzle housing, and an outer sprinkler nozzle pin part which is displaceably arranged in the sprinkler nozzle housing. Furthermore, the sprinkler nozzle pin parts are arranged coaxially in the passage in the sprinkler nozzle housing, so that the outer sprinkler pin part surrounds the inner sprinkler nozzle pin part. Thereby are provided sprinkler nozzles enabling the formation of sprinkler systems with a capacity of meeting the new and tightened requirements to fire protection of e.g. helipads. Likewise, the invention could eliminate the use of deluge guns. Other advantageous features of the invention appear from the claims and of the specification.